package com.cn.wanxi.util;

import com.alibaba.fastjson.JSONObject;
import com.cn.wanxi.model.ImgModel;
import com.cn.wanxi.model.ResultModel;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.PrintWriter;
import java.util.List;

public class ToolFileUpload {
    // 上传文件存储目录
    private static final String UPLOAD_DIRECTORY = "upload";
    private static final String SEPARATOR = "/";
    // 上传配置
    private static final int MEMORY_THRESHOLD = 1024 * 1024 * 3;  // 3MB
    private static final int MAX_FILE_SIZE = 1024 * 1024 * 40; // 40MB
    private static final int MAX_REQUEST_SIZE = 1024 * 1024 * 50; // 50MB

    public static String upload(HttpServletRequest req, HttpServletResponse resp) {
        try {
            // 检测是否为多媒体上传
            if (!ServletFileUpload.isMultipartContent(req)) {
                // 如果不是则停止
                PrintWriter writer = resp.getWriter();
                writer.println("Error: 表单必须包含 enctype=multipart/form-data");
                writer.flush();
                return "";
            }

            // 配置上传参数,内存里面开辟一个空间接受前端传递过来的文件
            DiskFileItemFactory factory = new DiskFileItemFactory();
            // 设置内存临界值 - 超过后将产生临时文件并存储于临时目录中
            factory.setSizeThreshold(MEMORY_THRESHOLD);
            // 设置临时存储目录
            factory.setRepository(new File(System.getProperty("java.io.tmpdir")));

//        用来解析文件的类
            ServletFileUpload upload = new ServletFileUpload(factory);

            // 设置最大文件上传值
            upload.setFileSizeMax(MAX_FILE_SIZE);

            // 设置最大请求值 (包含文件和表单数据)
            upload.setSizeMax(MAX_REQUEST_SIZE);

            // 中文处理
            upload.setHeaderEncoding("UTF-8");

            // 构造临时路径来存储上传的文件
            // 这个路径相对当前应用的目录
            String uploadPath = req.getServletContext().getRealPath("./") + File.separator + UPLOAD_DIRECTORY;

//我们需要将保存的路径：放入到web目录下
            // 如果目录不存在则创建
            createDirectory(uploadPath);


            // 解析请求的内容提取文件数据
            @SuppressWarnings("unchecked")
            List<FileItem> formItems = upload.parseRequest(req);

            if (formItems != null && formItems.size() > 0) {
                // 迭代表单数据
                for (FileItem item : formItems) {
                    // 处理不在表单中的字段
                    if (!item.isFormField()) {
                        String fileName = item.getName();
                        fileName = System.currentTimeMillis() + "--" + fileName;
//                        E:\wanxi\step-4\canyin04-0523\web +/+aa.jpg
                        String filePath = uploadPath + File.separator + fileName;
                        File storeFile = new File(filePath);
                        // 在控制台输出文件的上传路径
                        System.out.println(filePath);
                        // 保存文件到硬盘
                        item.write(storeFile);

                        String temp = uploadPath.split("out")[0] + "/web/" + UPLOAD_DIRECTORY;
                        createDirectory(temp);
                        String webPath = temp + SEPARATOR + fileName;
                        File webFile = new File(webPath);
                        item.write(webFile);
                        return SEPARATOR + UPLOAD_DIRECTORY + SEPARATOR + fileName;
                    }
                }
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
        return "";
    }

    private static void createDirectory(String uploadPath) {
        File uploadDir = new File(uploadPath);
        if (!uploadDir.exists()) {
            uploadDir.mkdirs();
        }
    }
}
